/*!
 * mustache.js - Logic-less {{mustache}} templates with JavaScript
 * http://github.com/janl/mustache.js
 */

var objectToString = Object.prototype.toString;
var isArray = Array.isArray || function isArrayPolyfill(object) {
    return objectToString.call(object) === '[object Array]';
};

function isFunction(object) {
    return typeof object === 'function';
}

/**
 * More correct typeof string handling array
 * which normally returns typeof 'object'
 */
function typeStr(obj) {
    return isArray(obj) ? 'array' : typeof obj;
}

function escapeRegExp(string) {
    return string.replace(/[\-\[\]{}()*+?.,\\\^$|#\s]/g, '\\$&');
}

/**
 * Null safe way of checking whether or not an object,
 * including its prototype, has a given property
 */
function hasProperty(obj, propName) {
    return obj != null && typeof obj === 'object' && (propName in obj);
}

/**
 * Safe way of detecting whether or not the given thing is a primitive and
 * whether it has the given property
 */
function primitiveHasOwnProperty(primitive, propName) {
    return (
        primitive != null
        && typeof primitive !== 'object'
        && primitive.hasOwnProperty
        && primitive.hasOwnProperty(propName)
    );
}

// Workaround for https://issues.apache.org/jira/browse/COUCHDB-577
// See https://github.com/janl/mustache.js/issues/189
var regExpTest = RegExp.prototype.test;
function testRegExp(re, string) {
    return regExpTest.call(re, string);
}

var nonSpaceRe = /\S/;
function isWhitespace(string) {
    return !testRegExp(nonSpaceRe, string);
}

var entityMap = {
    '&': '&amp;',
    '<': '&lt;',
    '>': '&gt;',
    '"': '&quot;',
    "'": '&#39;',
    '/': '&#x2F;',
    '`': '&#x60;',
    '=': '&#x3D;'
};

function escapeHtml(string) {
    return String(string).replace(/[&<>"'`=\/]/g, function fromEntityMap(s) {
        return entityMap[s];
    });
}

var whiteRe = /\s*/;
var spaceRe = /\s+/;
var equalsRe = /\s*=/;
var curlyRe = /\s*\}/;
var tagRe = /#|\^|\/|>|\{|&|=|!/;

/**
 * Breaks up the given `template` string into a tree of tokens. If the `tags`
 * argument is given here it must be an array with two string values: the
 * opening and closing tags used in the template (e.g. [ "<%", "%>" ]). Of
 * course, the default is to use mustaches (i.e. mustache.tags).
 *
 * A token is an array with at least 4 elements. The first element is the
 * mustache symbol that was used inside the tag, e.g. "#" or "&". If the tag
 * did not contain a symbol (i.e. {{myValue}}) this element is "name". For
 * all text that appears outside a symbol this element is "text".
 *
 * The second element of a token is its "value". For mustache tags this is
 * whatever else was inside the tag besides the opening symbol. For text tokens
 * this is the text itself.
 *
 * The third and fourth elements of the token are the start and end indices,
 * respectively, of the token in the original template.
 *
 * Tokens that are the root node of a subtree contain two more elements: 1) an
 * array of tokens in the subtree and 2) the index in the original template at
 * which the closing tag for that section begins.
 *
 * Tokens for partials also contain two more elements: 1) a string value of
 * indendation prior to that tag and 2) the index of that tag on that line -
 * eg a value of 2 indicates the partial is the third tag on this line.
 */
function parseTemplate(template, tags) {
    if (!template)
        return [];
    var lineHasNonSpace = false;
    var sections = [];     // Stack to hold section tokens
    var tokens = [];       // Buffer to hold the tokens
    var spaces = [];       // Indices of whitespace tokens on the current line
    var hasTag = false;    // Is there a {{tag}} on the current line?
    var nonSpace = false;  // Is there a non-space char on the current line?
    var indentation = '';  // Tracks indentation for tags that use it
    var tagIndex = 0;      // Stores a count of number of tags encountered on a line

    // Strips all whitespace tokens array for the current line
    // if there was a {{#tag}} on it and otherwise only space.
    function stripSpace() {
        if (hasTag && !nonSpace) {
            while (spaces.length)
                delete tokens[spaces.pop()];
        } else {
            spaces = [];
        }

        hasTag = false;
        nonSpace = false;
    }

    var openingTagRe, closingTagRe, closingCurlyRe;
    function compileTags(tagsToCompile) {
        if (typeof tagsToCompile === 'string')
            tagsToCompile = tagsToCompile.split(spaceRe, 2);

        if (!isArray(tagsToCompile) || tagsToCompile.length !== 2)
            throw new Error('Invalid tags: ' + tagsToCompile);

        openingTagRe = new RegExp(escapeRegExp(tagsToCompile[0]) + '\\s*');
        closingTagRe = new RegExp('\\s*' + escapeRegExp(tagsToCompile[1]));
        closingCurlyRe = new RegExp('\\s*' + escapeRegExp('}' + tagsToCompile[1]));
    }

    compileTags(tags || mustache.tags);

    var scanner = new Scanner(template);

    var start, type, value, chr, token, openSection;
    while (!scanner.eos()) {
        start = scanner.pos;

        // Match any text between tags.
        value = scanner.scanUntil(openingTagRe);

        if (value) {
            for (var i = 0, valueLength = value.length; i < valueLength; ++i) {
                chr = value.charAt(i);

                if (isWhitespace(chr)) {
                    spaces.push(tokens.length);
                    indentation += chr;
                } else {
                    nonSpace = true;
                    lineHasNonSpace = true;
                    indentation += ' ';
                }

                tokens.push(['text', chr, start, start + 1]);
                start += 1;

                // Check for whitespace on the current line.
                if (chr === '\n') {
                    stripSpace();
                    indentation = '';
                    tagIndex = 0;
                    lineHasNonSpace = false;
                }
            }
        }

        // Match the opening tag.
        if (!scanner.scan(openingTagRe))
            break;

        hasTag = true;

        // Get the tag type.
        type = scanner.scan(tagRe) || 'name';
        scanner.scan(whiteRe);

        // Get the tag value.
        if (type === '=') {
            value = scanner.scanUntil(equalsRe);
            scanner.scan(equalsRe);
            scanner.scanUntil(closingTagRe);
        } else if (type === '{') {
            value = scanner.scanUntil(closingCurlyRe);
            scanner.scan(curlyRe);
            scanner.scanUntil(closingTagRe);
            type = '&';
        } else {
            value = scanner.scanUntil(closingTagRe);
        }

        // Match the closing tag.
        if (!scanner.scan(closingTagRe))
            throw new Error('Unclosed tag at ' + scanner.pos);

        if (type == '>') {
            token = [type, value, start, scanner.pos, indentation, tagIndex, lineHasNonSpace];
        } else {
            token = [type, value, start, scanner.pos];
        }
        tagIndex++;
        tokens.push(token);

        if (type === '#' || type === '^') {
            sections.push(token);
        } else if (type === '/') {
            // Check section nesting.
            openSection = sections.pop();

            if (!openSection)
                throw new Error('Unopened section "' + value + '" at ' + start);

            if (openSection[1] !== value)
                throw new Error('Unclosed section "' + openSection[1] + '" at ' + start);
        } else if (type === 'name' || type === '{' || type === '&') {
            nonSpace = true;
        } else if (type === '=') {
            // Set the tags for the next time around.
            compileTags(value);
        }
    }

    stripSpace();

    // Make sure there are no open sections when we're done.
    openSection = sections.pop();

    if (openSection)
        throw new Error('Unclosed section "' + openSection[1] + '" at ' + scanner.pos);

    let Tokens = nestTokens(squashTokens(tokens));
    console.log(Tokens)
    return Tokens;
}

/**
 * Combines the values of consecutive text tokens in the given `tokens` array
 * to a single token.
 */
function squashTokens(tokens) {
    var squashedTokens = [];

    var token, lastToken;
    for (var i = 0, numTokens = tokens.length; i < numTokens; ++i) {
        token = tokens[i];

        if (token) {
            if (token[0] === 'text' && lastToken && lastToken[0] === 'text') {
                lastToken[1] += token[1];
                lastToken[3] = token[3];
            } else {
                squashedTokens.push(token);
                lastToken = token;
            }
        }
    }

    return squashedTokens;
}

/**
 * Forms the given array of `tokens` into a nested tree structure where
 * tokens that represent a section have two additional items: 1) an array of
 * all tokens that appear in that section and 2) the index in the original
 * template that represents the end of that section.
 */
function nestTokens(tokens) {
    var nestedTokens = [];
    var collector = nestedTokens;
    var sections = [];

    var token, section;
    for (var i = 0, numTokens = tokens.length; i < numTokens; ++i) {
        token = tokens[i];

        switch (token[0]) {
            case '#':
            case '^':
                collector.push(token);
                sections.push(token);
                collector = token[4] = [];
                break;
            case '/':
                section = sections.pop();
                section[5] = token[2];
                collector = sections.length > 0 ? sections[sections.length - 1][4] : nestedTokens;
                break;
            default:
                collector.push(token);
        }
    }

    return nestedTokens;
}

/**
 * A simple string scanner that is used by the template parser to find
 * tokens in template strings.
 */
function Scanner(string) {
    this.string = string;
    this.tail = string;
    this.pos = 0;
}

/**
 * Returns `true` if the tail is empty (end of string).
 */
Scanner.prototype.eos = function eos() {
    return this.tail === '';
};

/**
 * Tries to match the given regular expression at the current position.
 * Returns the matched text if it can match, the empty string otherwise.
 */
Scanner.prototype.scan = function scan(re) {
    var match = this.tail.match(re);

    if (!match || match.index !== 0)
        return '';

    var string = match[0];

    this.tail = this.tail.substring(string.length);
    this.pos += string.length;

    return string;
};

/**
 * Skips all text until the given regular expression can be matched. Returns
 * the skipped string, which is the entire tail if no match can be made.
 */
Scanner.prototype.scanUntil = function scanUntil(re) {
    var index = this.tail.search(re), match;

    switch (index) {
        case -1:
            match = this.tail;
            this.tail = '';
            break;
        case 0:
            match = '';
            break;
        default:
            match = this.tail.substring(0, index);
            this.tail = this.tail.substring(index);
    }

    this.pos += match.length;

    return match;
};

/**
 * Represents a rendering context by wrapping a view object and
 * maintaining a reference to the parent context.
 */
function Context(view, parentContext) {
    this.view = view;
    this.cache = { '.': this.view };
    this.parent = parentContext;
}

/**
 * Creates a new context using the given view with this context
 * as the parent.
 */
Context.prototype.push = function push(view) {
    return new Context(view, this);
};

/**
 * Returns the value of the given name in this context, traversing
 * up the context hierarchy if the value is absent in this context's view.
 */
Context.prototype.lookup = function lookup(name) {
    var cache = this.cache;

    var value;
    if (cache.hasOwnProperty(name)) {
        value = cache[name];
    } else {
        var context = this, intermediateValue, names, index, lookupHit = false;

        while (context) {
            if (name.indexOf('.') > 0) {
                intermediateValue = context.view;
                names = name.split('.');
                index = 0;

                /**
                 * Using the dot notion path in `name`, we descend through the
                 * nested objects.
                 *
                 * To be certain that the lookup has been successful, we have to
                 * check if the last object in the path actually has the property
                 * we are looking for. We store the result in `lookupHit`.
                 *
                 * This is specially necessary for when the value has been set to
                 * `undefined` and we want to avoid looking up parent contexts.
                 *
                 * In the case where dot notation is used, we consider the lookup
                 * to be successful even if the last "object" in the path is
                 * not actually an object but a primitive (e.g., a string, or an
                 * integer), because it is sometimes useful to access a property
                 * of an autoboxed primitive, such as the length of a string.
                 **/
                while (intermediateValue != null && index < names.length) {
                    if (index === names.length - 1)
                        lookupHit = (
                            hasProperty(intermediateValue, names[index])
                            || primitiveHasOwnProperty(intermediateValue, names[index])
                        );

                    intermediateValue = intermediateValue[names[index++]];
                }
            } else {
                intermediateValue = context.view[name];

                /**
                 * Only checking against `hasProperty`, which always returns `false` if
                 * `context.view` is not an object. Deliberately omitting the check
                 * against `primitiveHasOwnProperty` if dot notation is not used.
                 *
                 * Consider this example:
                 * ```
                 * Mustache.render("The length of a football field is {{#length}}{{length}}{{/length}}.", {length: "100 yards"})
                 * ```
                 *
                 * If we were to check also against `primitiveHasOwnProperty`, as we do
                 * in the dot notation case, then render call would return:
                 *
                 * "The length of a football field is 9."
                 *
                 * rather than the expected:
                 *
                 * "The length of a football field is 100 yards."
                 **/
                lookupHit = hasProperty(context.view, name);
            }

            if (lookupHit) {
                value = intermediateValue;
                break;
            }

            context = context.parent;
        }

        cache[name] = value;
    }

    if (isFunction(value))
        value = value.call(this.view);

    return value;
};

/**
 * A Writer knows how to take a stream of tokens and render them to a
 * string, given a context. It also maintains a cache of templates to
 * avoid the need to parse the same template twice.
 */
function Writer() {
    this.templateCache = {
        _cache: {},
        set: function set(key, value) {
            this._cache[key] = value;
        },
        get: function get(key) {
            return this._cache[key];
        },
        clear: function clear() {
            this._cache = {};
        }
    };
}

/**
 * Clears all cached templates in this writer.
 */
Writer.prototype.clearCache = function clearCache() {
    if (typeof this.templateCache !== 'undefined') {
        this.templateCache.clear();
    }
};

/**
 * Parses and caches the given `template` according to the given `tags` or
 * `mustache.tags` if `tags` is omitted,  and returns the array of tokens
 * that is generated from the parse.
 */
Writer.prototype.parse = function parse(template, tags) {
    var cache = this.templateCache;
    var cacheKey = template + ':' + (tags || mustache.tags).join(':');
    var isCacheEnabled = typeof cache !== 'undefined';
    var tokens = isCacheEnabled ? cache.get(cacheKey) : undefined;

    if (tokens == undefined) {
        tokens = parseTemplate(template, tags);
        isCacheEnabled && cache.set(cacheKey, tokens);
    }
    return tokens;
};

/**
 * High-level method that is used to render the given `template` with
 * the given `view`.
 *
 * The optional `partials` argument may be an object that contains the
 * names and templates of partials that are used in the template. It may
 * also be a function that is used to load partial templates on the fly
 * that takes a single argument: the name of the partial.
 *
 * If the optional `config` argument is given here, then it should be an
 * object with a `tags` attribute or an `escape` attribute or both.
 * If an array is passed, then it will be interpreted the same way as
 * a `tags` attribute on a `config` object.
 *
 * The `tags` attribute of a `config` object must be an array with two
 * string values: the opening and closing tags used in the template (e.g.
 * [ "<%", "%>" ]). The default is to mustache.tags.
 *
 * The `escape` attribute of a `config` object must be a function which
 * accepts a string as input and outputs a safely escaped string.
 * If an `escape` function is not provided, then an HTML-safe string
 * escaping function is used as the default.
 */
Writer.prototype.render = function render(template, view, partials, config) {
    var tags = this.getConfigTags(config);
    var tokens = this.parse(template, tags);
    var context = (view instanceof Context) ? view : new Context(view, undefined);
    return this.renderTokens(tokens, context, partials, template, config);
};

/**
 * Low-level method that renders the given array of `tokens` using
 * the given `context` and `partials`.
 *
 * Note: The `originalTemplate` is only ever used to extract the portion
 * of the original template that was contained in a higher-order section.
 * If the template doesn't use higher-order sections, this argument may
 * be omitted.
 */
Writer.prototype.renderTokens = function renderTokens(tokens, context, partials, originalTemplate, config) {
    var buffer = '';

    var token, symbol, value;
    for (var i = 0, numTokens = tokens.length; i < numTokens; ++i) {
        value = undefined;
        token = tokens[i];
        symbol = token[0];

        if (symbol === '#') value = this.renderSection(token, context, partials, originalTemplate, config);
        else if (symbol === '^') value = this.renderInverted(token, context, partials, originalTemplate, config);
        else if (symbol === '>') value = this.renderPartial(token, context, partials, config);
        else if (symbol === '&') value = this.unescapedValue(token, context);
        else if (symbol === 'name') value = this.escapedValue(token, context, config);
        else if (symbol === 'text') value = this.rawValue(token);

        if (value !== undefined)
            buffer += value;
    }

    return buffer;
};

Writer.prototype.renderSection = function renderSection(token, context, partials, originalTemplate, config) {
    var self = this;
    var buffer = '';
    var value = context.lookup(token[1]);

    // This function is used to render an arbitrary template
    // in the current context by higher-order sections.
    function subRender(template) {
        return self.render(template, context, partials, config);
    }

    if (!value) return;

    if (isArray(value)) {
        for (var j = 0, valueLength = value.length; j < valueLength; ++j) {
            buffer += this.renderTokens(token[4], context.push(value[j]), partials, originalTemplate, config);
        }
    } else if (typeof value === 'object' || typeof value === 'string' || typeof value === 'number') {
        buffer += this.renderTokens(token[4], context.push(value), partials, originalTemplate, config);
    } else if (isFunction(value)) {
        if (typeof originalTemplate !== 'string')
            throw new Error('Cannot use higher-order sections without the original template');

        // Extract the portion of the original template that the section contains.
        value = value.call(context.view, originalTemplate.slice(token[3], token[5]), subRender);

        if (value != null)
            buffer += value;
    } else {
        buffer += this.renderTokens(token[4], context, partials, originalTemplate, config);
    }
    return buffer;
};

Writer.prototype.renderInverted = function renderInverted(token, context, partials, originalTemplate, config) {
    var value = context.lookup(token[1]);

    // Use JavaScript's definition of falsy. Include empty arrays.
    // See https://github.com/janl/mustache.js/issues/186
    if (!value || (isArray(value) && value.length === 0))
        return this.renderTokens(token[4], context, partials, originalTemplate, config);
};

Writer.prototype.indentPartial = function indentPartial(partial, indentation, lineHasNonSpace) {
    var filteredIndentation = indentation.replace(/[^ \t]/g, '');
    var partialByNl = partial.split('\n');
    for (var i = 0; i < partialByNl.length; i++) {
        if (partialByNl[i].length && (i > 0 || !lineHasNonSpace)) {
            partialByNl[i] = filteredIndentation + partialByNl[i];
        }
    }
    return partialByNl.join('\n');
};

Writer.prototype.renderPartial = function renderPartial(token, context, partials, config) {
    if (!partials) return;
    var tags = this.getConfigTags(config);

    var value = isFunction(partials) ? partials(token[1]) : partials[token[1]];
    if (value != null) {
        var lineHasNonSpace = token[6];
        var tagIndex = token[5];
        var indentation = token[4];
        var indentedValue = value;
        if (tagIndex == 0 && indentation) {
            indentedValue = this.indentPartial(value, indentation, lineHasNonSpace);
        }
        var tokens = this.parse(indentedValue, tags);
        return this.renderTokens(tokens, context, partials, indentedValue, config);
    }
};

Writer.prototype.unescapedValue = function unescapedValue(token, context) {
    var value = context.lookup(token[1]);
    if (value != null)
        return value;
};

Writer.prototype.escapedValue = function escapedValue(token, context, config) {
    var escape = this.getConfigEscape(config) || mustache.escape;
    var value = context.lookup(token[1]);
    if (value != null)
        return (typeof value === 'number' && escape === mustache.escape) ? String(value) : escape(value);
};

Writer.prototype.rawValue = function rawValue(token) {
    return token[1];
};

Writer.prototype.getConfigTags = function getConfigTags(config) {
    if (isArray(config)) {
        return config;
    }
    else if (config && typeof config === 'object') {
        return config.tags;
    }
    else {
        return undefined;
    }
};

Writer.prototype.getConfigEscape = function getConfigEscape(config) {
    if (config && typeof config === 'object' && !isArray(config)) {
        return config.escape;
    }
    else {
        return undefined;
    }
};

var mustache = {
    name: 'mustache.js',
    version: '4.2.0',
    tags: ['{{', '}}'],
    clearCache: undefined,
    escape: undefined,
    parse: undefined,
    render: undefined,
    Scanner: undefined,
    Context: undefined,
    Writer: undefined,
    /**
     * Allows a user to override the default caching strategy, by providing an
     * object with set, get and clear methods. This can also be used to disable
     * the cache by setting it to the literal `undefined`.
     */
    set templateCache(cache) {
        defaultWriter.templateCache = cache;
    },
    /**
     * Gets the default or overridden caching object from the default writer.
     */
    get templateCache() {
        return defaultWriter.templateCache;
    }
};

// All high-level mustache.* functions use this writer.
var defaultWriter = new Writer();

/**
 * Clears all cached templates in the default writer.
 */
mustache.clearCache = function clearCache() {
    return defaultWriter.clearCache();
};

/**
 * Parses and caches the given template in the default writer and returns the
 * array of tokens it contains. Doing this ahead of time avoids the need to
 * parse templates on the fly as they are rendered.
 */
mustache.parse = function parse(template, tags) {
    return defaultWriter.parse(template, tags);
};

/**
 * Renders the `template` with the given `view`, `partials`, and `config`
 * using the default writer.
 */
mustache.render = function render(template, view, partials, config) {
    if (typeof template !== 'string') {
        throw new TypeError('Invalid template! Template should be a "string" ' +
            'but "' + typeStr(template) + '" was given as the first ' +
            'argument for mustache#render(template, view, partials)');
    }

    return defaultWriter.render(template, view, partials, config);
};

// Export the escaping function so that the user may override it.
// See https://github.com/janl/mustache.js/issues/244
mustache.escape = escapeHtml;

// Export these mainly for testing, but also for advanced usage.
mustache.Scanner = Scanner;
mustache.Context = Context;
mustache.Writer = Writer;

export default mustache;